11.5 digestive system Flashcards
ameoba
phagocytosis form vacuoles then fuse with lysosomes
paramecium
cilia sweet food and form vacuoles
annelids
crop for storage, gizzard for grinding food and intestine has typhlosole for SA
arthropods
have jaws and salivary glands
molluscs
have radula in mouth
mesenteries in human
fat connective tissue that give support and blood supply to digestive system
stomach structure
bolus enters through lower esophageal or cardiac sphincter. have exocrine glands in gastric pits (indentations with chief cells, parietal cells, g cells and mucous cells)
stomach digestion
chyme is food with gastric juice. pepsinogen comes from chief cells (then pepsin in low pH), parietal cells secrete Hal and g cells secrete gastrin (hormone to release HCl)
pH is 2
- has rural folds for SA
acetylcholine does what to GI?
increases secretion of all cells in stomach
small intestine
food goes here through pyloric sphincter. first duodenum breaks down stuff then absorption in jejunum and lieum.
ileum contains
pewter’s patches of lymph tissue
lacteal
lymph around capillary network. present in small Intestine
goblet cells
secrete mucous
duodenum ph
6 from bicarbonate from pancreas and trypsin and chymotrypsin (protease)
trypsin activation
all enzymes from pancreases are inactive until trypsin activates them
liver
makes bile. stored in gall bladder. this merges with pancreas. bile breaks up fats
sphincter of oddi
where pancreas meets duodenum
large intestine
Food enters through ileocecal valve. reabsorbs water and makes faces. bacteria help make vitamins here Ie E. coli for vitamin K
gastrin hormone
produced by stomach when sensing food
secretin
produced by duodenum from HCl. nudges pancreas
cholecystokinin
secreted by SI to gat digest and nudges gall bladder
gastric inhibitory peptide
decrease stomach activity for fat digestion
enterogastronone
any hormone done in response to fats or lipids that slows digestion
grehlin
stimulates hunder
leptin, pYY insuline and epinphrine
suppress hunger from adipose tissue, SI, pancreas
blood filtration in liver
Kupfer cells (specialized macrophages in liver) phagocytize bacteria picked up in intestines. also destroys irregular blood cells
Carbohydrate Metabolism in liver
– Liver maintains normal blood glucose levels via gluconeogenesis
(production of glycogen and glucose from noncarb precursors), glycogenesis, and storage of
glycogen (not glucose, it stores as glycogen!)
Fat metabolism in liver
Liver synthesizes bile from cholesterol and converts carbs + proteins
fat.
Oxidizes fatty acids for energy. Forms lipoproteins.
Protein metabolism in liver
Liver deaminates AA’s, forms urea from ammonia in blood, synths plasma
proteins, synths nonessential AAs
liver and vitamin storage
stores vitamins
Glycogenesis
(formation of glycogen)
glycogenolysis
(if blood glucose levels decrease
glycogen broken down to glu for release)
blood acidity and liver
When liver mobilizes fat or protein for energy, blood acidity increases (ketone bodies are
produced ketosis/acidosis results)
jaundice
liver malfxn can lead to jaundice: yellow pigmentation from excess bilirubin (byproduct of
erythrocyte breakdown);
Anne lids have
Typhlosole for sa
Mucous cells secrete
Musics in stomach lining
Chief cells secrete
Pepsinogen that gets activated to pepsin by pH
Parietal cells secrete
Hcl
G cells
Secrete gastric. Stimulates parietal cell to secrete hcl
Liver produces
Bile
